SEPA direct debit payments now consistently use the recurring payment status instead of marking initial payments separately. This aligns payment files with current banking rules and helps avoid unnecessary processing differences for French direct debit transactions.

## The issue:
'FRST' is the code use for the first transaction. Every following
transaction should have the code 'RCUR'.
Moreover, since 2016, 'FRST' isn't even required anymore.

## The fix:
Simply replace 'FRST' by 'RCUR'

### Ticket: \#2490238

Payslip creation now prevents users from selecting a cancelled employee contract, even when the payslip dates would otherwise match it. This helps payroll teams avoid processing pay based on invalid contracts and reduces the risk of payroll mistakes.

Currently, when creating a payslip, if the dates allow it, you can
select a cancelled contract to base your payslip on. This shouldn't be
the case.

Task ID: 2501310

Payroll users can now edit multiple payslips directly from the list view, making bulk payroll adjustments faster and easier. A related automatic update behavior was removed to avoid issues when making changes across several payslips at once.

Allow batch edit on payslips tree view.

Also removes an onchange that could cause issue when editing in batch.

Task Id: 2501306

Payroll users can now add a payslip to a batch that has already been marked as paid. This helps handle exceptions, such as an employee who was missed in the original payment run, without creating a separate workaround.

Currently it is not possible to add a payslip in a paid batch.
But for example if an employee hasn't been paid, we want to be able to
add it's payslip to an already done batch.

Task Id: 2501307